Epidemiology and Prevention Division, Research Center for Cancer Prevention and Screening, National Cancer Center, 5-1-1 Tsukiji, Tokyo, 104-0045, Japan.
Prev Med. 2011 Mar-Apr;52(3-4):227-33. doi: 10.1016/j.ypmed.2011.01.016. Epub 2011 Feb 2.
The study aims to investigate the association between leisure-time physical activity and breast cancer risk in consideration of tumor estrogen-receptor/progesterone-receptor status.
We conducted a population-based prospective cohort study among 53,578 women in the Japan Public Health Center-based Prospective Study. Leisure-time physical activity was assessed by self-reported questionnaires. A Cox proportional hazards regression model was used to derive relative risks and 95% confidence intervals.
From 1990-1993 to the end of 2007, 652 cases were identified. The breast cancer rates (per 100,000 person-years) in the sedentary groups (≤3 days/month) was 84 in overall, 97 in premenopausal and 75 in postmenopausal women. We observed a statistically significant inverse association between leisure-time physical activity and breast cancer risk (relative risk(≥3 days/week vs. ≤3 days/month)=0.73; 95% confidence interval 0.54-1.00; p(trend) 0.037), particularly in estrogen receptor+progesterone receptor+ (relative risk 0.43; 0.19-1.00; p(trend) 0.022), and this inverse trend was apparent among postmenopausal women (relative risk 0.25; 0.06-1.06; p(trend) 0.041). An inverse trend was also observed between daily total physical activity and postmenopausal estrogen receptor+progesterone receptor+ risk (p=0.046). Among body mass index ≥25 kg/m(2) group, leisure-time physical activity was associated with decreased risk (relative risk(≥1 day/week vs. ≤3 days/month)=0.65; 0.43-0.97; p(trend) 0.033).
Active participation in leisure-time physical activity may contribute to a decrease in breast cancer risk, particularly for postmenopausal estrogen receptor+progesterone receptor+ tumors.
本研究旨在探讨考虑肿瘤雌激素受体/孕激素受体状态下，休闲时间体力活动与乳腺癌风险之间的关联。
我们在日本公共卫生中心前瞻性研究中对 53578 名女性进行了一项基于人群的前瞻性队列研究。休闲时间体力活动通过自我报告的问卷进行评估。使用 Cox 比例风险回归模型得出相对风险和 95%置信区间。
从 1990-1993 年至 2007 年底，共发现 652 例病例。久坐不动组（≤3 天/月）的乳腺癌发病率（每 100000 人年）分别为总人群 84 例，绝经前妇女 97 例和绝经后妇女 75 例。我们观察到休闲时间体力活动与乳腺癌风险之间存在统计学上显著的负相关（每周≥3 天与每月≤3 天相比，相对风险=0.73；95%置信区间 0.54-1.00；p 趋势=0.037），特别是在雌激素受体+孕激素受体+的患者中（相对风险 0.43；0.19-1.00；p 趋势=0.022），并且这种负向趋势在绝经后妇女中更为明显（相对风险 0.25；0.06-1.06；p 趋势=0.041）。每天总体力活动与绝经后雌激素受体+孕激素受体+风险之间也观察到负向趋势（p=0.046）。在 BMI≥25kg/m2 组中，休闲时间体力活动与降低风险相关（每周≥1 天与每月≤3 天相比，相对风险=0.65；0.43-0.97；p 趋势=0.033）。
积极参与休闲时间体力活动可能有助于降低乳腺癌风险，特别是绝经后雌激素受体+孕激素受体+肿瘤。
